Hedge fund manager Christopher Hansen plans to buy a basketball team and move it to Seattle, where it would play in an arena he hopes to build, city officials said yesterday.

Hansen, who runs San Francisco-based Valiant Capital Management, has proposed a nearly $500 million new arena in Seattle's SoDo neighborhood, near the homes of football's Seattle Seahawks and baseball's Seattle Mariners. He even owns the three-acre plot he's got in mind for the building.

What Hansen does not yet own is a team—Seattle Mayor Mike McGinn and King County Executive Dow Constantine warned that the hedge fund manager will not move forward with his plans unless there's a team with a lease to play in the arena.

Speculation has centered on the Sacramento Kings; California's capital city has until the end of the month to come up with plans for a new arena there if it hopes to keep the team. City and county officials added that Hansen hoped to lure a hockey team to the city if the arena is built.

Seattle has been without professional basketball since 2008, when the former SuperSonics decamped to Oklahoma City amidst a battle over public financing for a new arena. Hansen has made clear that his arena would be primarily privately funded; McGinn said that Hansen would raise $290 million in private investments to build the arena and another $200 million or so to buy a National Basketball Association team. The city would kick in $200 million towards the arena, using tax revenues the building generates and rental income paid by the teams who play there.

The mayor and county executive said they would submit Hansen's plan to a 10-member advisory panel for review.